The goal of this new project is to study genetic competence (competent for genetic transformation) induction in Streptococcus gordonii as a model system for global genetic regulation in the oral strptococci. Standard molecular genetic techniques are being utilized to isolate genes specifically induced at competence and to characterize the gene products responsible for DNA uptake and processing. This activity will provide a set of developmentally induced loci with which to begin a systematic investigation of specialized gene expression in this genera. A second major aim of the project is to determine what role genetic transformation may play in the horizontal transfer of genetic information within the streptococcal compartment of the oral microbiota. These studies will determine whether competence has any relevance to antigenic variation and the overall genetic fitness for oral colonization by this group of organisms.